Mosses and Lichens 



texture, in colour, and in the nature of the margin, this being 

 sometimes entire, and sometimes toothed, sometimes with a 

 thickened margin or with one made up of cells very different 

 from those within. 



The species of mosses are based on the characters of the 

 plant, the spore-case, the pedicel, and the leaves, together with 

 their habit of growth. 



Everything about the moss-plants indicates that their purpose 

 in living is to reproduce their kind. Each part is designed and 

 perfected with this end in view. In the struggle for existence 

 they have come to adapt themselves to the most varied condi- 

 tions, but a certain amount of water is as necessary to them as to 

 all other forms of life. Without water the male cells can never 

 reach the egg-cells and the leaf-green (chlorophyll) cannot manu- 

 facture plant food. It is true that there are species which have 

 ceased to attempt the formation of spores in localities where the 

 rainy season is never long enough to permit their reaching 

 maturity. In such species the plants become very dry, the leaves 



Funaria hy- 

 trometrica. With 

 an immature 

 spore-case cov- 

 ered by its veil. ' 



Polylrichum 

 brachyphyllum. 

 Spore-case with 

 hairy veil 



Fissidens adi- 

 antoides. Spore- 

 case with one 

 row of teeth. 



Dicrantlla heteromdla. Spore-case 

 with and without a veil. 



Polytrich- 

 um pilifer- 

 um. Leaf 

 with apex 

 prolonged 

 into an 

 awn. 



Gtorgia 

 geniculata. 



Spore -case 

 with four 

 teeth. 



